[Maxx134]

I'm going to replace these with OCC silver which might be just the job for that particular problem to give it that bit more edge, which the other amp has got

Up to you...
Silver may make some benifits,
But the main problem of stock amp wiring,
was the thin guage output wire from board to sockets.

There are many more informed members over at other DIY forums,
But I haven't seen any give info about how circuit choices affect sonics yet.

So, I will tell from my experience::

*** Tube and bias selection help with clarity, dynamics, and soundStage..

***Coupling cap deal with overall signature and tonality plus soundStage.

***Cathode cap electrolytic boosts ouput, strengths bass when increased, and also can affect upper range signature detrimentally so need a bypass cap to help.

***WCF caps will make a slight difference in tonal balance, by adding harmonics and limiting soundstage , which is why I will be looking for some brighter and better caps there.

For example, The Mundorf I had at WCF position, made the amp sweeter with a slight larger stage over my "Vitamin Q" caps which gave a more dynamic livelier sound with smoother top and less sparkle.

So, unfortunately, any amp that uses caps will have to deal with and are limited by them.
Yet the "realism" level on this amp, I found is has more to do with tube selection and bias points.

I believe the driver stage in stock form is holding the amp back.
IMHO it needs the bias increase.

Hopefully we will find out just how much NFB we can reduce without adverse affecting sound.

My guess is that the driver tube choice will make the difference here.

Hopefully will start testing soon.

 

[Maxx134]

I don't know what you think with your comparisons with other amps?

(Correction) "Some" of the best tube amps I heard.
They had a bit more soundstage over mine.
They had a more controlled bass over mine.
They had more power as I have an MK8.
As far as realism, I could not make a call as mine falls at same level, and they all vary in harmonic signature (euphony).

This is why I believe the MK6 moded can achieve a top status potential.

If it not as "resolving" , and bias points were already adjusted, then I would say the caps are holding it back.

 

[klnglim]

That is what cap value upgrade is for.



My simplified schematic of the PSU did not go that far to show that section.

I believe that section is for power to the opamp circuit.
I would check with Coinmaster diagrams:
testing a paralled connection not change importance of different values as they are most likely branching out to different circuit areas of board.
Its still good that you noticed as you become more familiar with the circuits.

This amp so far what I have noticed is build into 2 section, there are PSU B+ B- stage and tube driver sound stage.
It's not very difficult to build DIY prototype, the parts are quite cheap and easy to get replacement and upgrade
The amp is amazing design, I have learned a lot after get into deeper, look inside all of it and not much $$$ spending overall total but spend a lot of time to study or to understand
Most important is thanks to this forum's members for their sharing, knowledge and support, really help a lot and wonderful experience

 

[baronbeehive]

Up to you...
Silver may make some benifits,
But the main problem of stock amp wiring,
was the thin guage output wire from board to sockets.

There are many more informed members over at other DIY forums,
But I haven't seen any give info about how circuit choices affect sonics yet.

Yes, its a long shot but for the specific thing I mention about those sybillant frequencies it just might help bringing the qualities of OCC silver wiring. As you know I rave about the other amp and it is in comparisons with it that I picked up this about the LD, which in other respects is top class.

So, I will tell from my experience::

*** Tube and bias selection help with clarity, dynamics, and soundStage..

***Coupling cap deal with overall signature and tonality plus soundStage.

***Cathode cap electrolytic boosts ouput, strengths bass when increased, and also can affect upper range signature detrimentally so need a bypass cap to help.

***WCF caps will make a slight difference in tonal balance, by adding harmonics and limiting soundstage , which is why I will be looking for some brighter and better caps there.

For example, The Mundorf I had at WCF position, made the amp sweeter with a slight larger stage over my "Vitamin Q" caps which gave a more dynamic livelier sound with smoother top and less sparkle.

So, unfortunately, any amp that uses caps will have to deal with and are limited by them.
Yet the "realism" level on this amp, I found is has more to do with tube selection and bias points.

I believe the driver stage in stock form is holding the amp back.
IMHO it needs the bias increase.

Hopefully we will find out just how much NFB we can reduce without adverse affecting sound.

My guess is that the driver tube choice will make the difference here.

I agree with you about all of this from my experience of modding both amps. I have the S/O Mundorf caps in WCF position so I think I have the best choice there for what I want.

(Correction) "Some" of the best tube amps I heard.
They had a bit more soundstage over mine.
They had a more controlled bass over mine.
They had more power as I have an MK8.
As far as realism, I could not make a call as mine falls at same level, and they all vary in harmonic signature (euphony).

This is why I believe the MK6 moded can achieve a top status potential.

If it not as "resolving" , and bias points were already adjusted, then I would say the caps are holding it back.

That's interesting, that is pretty much what I would expect from what I can imagine not having heard these top class amps. I'm not sure of the SS aspects of the circuitry in the APPJ but the bass is very controlled in that amp and the newer driver tubes really make it special, both the Philips and the Mazda are tight in bass, in comparison with the Tungsol for example, which is still pretty damn good. Don't know what you think about this with your APPJ.

 

[baronbeehive]

This amp so far what I have noticed is build into 2 section, there are PSU B+ B- stage and tube driver sound stage.
It's not very difficult to build DIY prototype, the parts are quite cheap and easy to get replacement and upgrade
The amp is amazing design, I have learned a lot after get into deeper, look inside all of it and not much $$$ spending overall total but spend a lot of time to study or to understand
Most important is thanks to this forum's members for their sharing, knowledge and support, really help a lot and wonderful experience

You will soon be designing and building your own custom amps LOL!

 

[Maxx134]

. I have the S/O Mundorf caps in WCF position so I think I have the best choice there for what I want

Actually, the bypass cap of the cathode cap would change top end tonality for you.

 

[klnglim]

Actually, the bypass cap of the cathode cap would change top end tonality for you.

Just want to know if I use Mundolf Evo Oil in coupling, and decoupling, Mundolf Evo in WCF, are there suitable? The idea use all Evo is because of the caps are a lot cheaper and size fit perfectly inside the amp

 

[Maxx134]

Just want to know if I use Mundolf Evo Oil in coupling, and decoupling, Mundolf Evo in WCF, are there suitable? The idea use all Evo is because of the caps are a lot cheaper and size fit perfectly inside the amp

They are very good.

They are all above average nice caps:

Good choice.
Coupling & WCF is more noticable than Decoupling..

 

[klnglim]

They are very good.

They are all above average nice caps:

Good choice.
Coupling & WCF is more noticable than Decoupling..

yes, those are the caps size fit perfectly and price a lot cheaper, That's why I asked before order

 

[baronbeehive]

Actually, the bypass cap of the cathode cap would change top end tonality for you.

Funnily enough I was only thinking about that yesterday, as I have the Audyn True Copper in the other amp, same as you. I didn't think the tone difference in the 2 amps was because of the Jupiter caps because I have the same in both amps. Also when I put the Audyn bypass caps in after a while without them the sound difference in the treble was massive. Don't know if they would fit though.

I might change the cathode caps to Kaisei as well if you note any differences, I have 2 spare.

Listening to the other amp yesterday, the guitar sound really rings out wonderfully, especially the treble register, but it is in no way sybillant. And there is a real edge to the transients which you can almost feel.

 

[Maxx134]

I didn't think the tone difference in the 2 amps was because of the Jupiter caps

That's because coupling cap position not supposed to affect FR.

The Cathode caps, on the other hand,
does affect tonality.

Just place another smaller cap in area, like a .01uf-.02uf so it is a decimal point over from your existing .1uf Rifa that we chose in beginning to bypass.

I don't want to affect the natural presentation that cap gives, only to give more top end air.

So I will be doing the same to get more sparkle,
because I want to expand soundStage detail cues, but naturally so I will a carfully choosen cap.

So caps uograde, and NFB reduction will be my next challenge.

My MK8 currently has holography in spades, and only needs more tweaks to be comparable to what I have been hearing from top amps,
Which is soundstage presentation and cleaner lower end.

That being said, I still plan to try make another amp this summer.

 

[baronbeehive]

That's because coupling cap position not supposed to affect FR.

The Cathode caps, on the other hand,
does affect tonality.

Just place another smaller cap in area, like a .01uf-.02uf so it is a decimal point over from your existing .1uf Rifa that we chose in beginning to bypass.

I don't want to affect the natural presentation that cap gives, only to give more top end air.

So I will be doing the same to get more sparkle,
because I want to expand soundStage detail cues, but naturally so I will a carfully choosen cap.

So caps uograde, and NFB reduction will be my next challenge.

Right I will try that later. Should be interesting!

My MK8 currently has holography in spades, and only needs more tweaks to be comparable to what I have been hearing from top amps,
Which is soundstage presentation and cleaner lower end.

That being said, I still plan to try make another amp this summer.

Yes, holography.... front to back, side to side, top to bottom is excellent in this amp, as soon as you put on those headphones to experience this you notice it..... and the spatial seperation.

Good luck with your build, summer is not the time for me to attempt something like that though LOL.

 

[klnglim]

That's because coupling cap position not supposed to affect FR.

The Cathode caps, on the other hand,
does affect tonality.

Just place another smaller cap in area, like a .01uf-.02uf so it is a decimal point over from your existing .1uf Rifa that we chose in beginning to bypass.

I don't want to affect the natural presentation that cap gives, only to give more top end air.

So I will be doing the same to get more sparkle,
because I want to expand soundStage detail cues, but naturally so I will a carfully choosen cap.

So caps uograde, and NFB reduction will be my next challenge.

My MK8 currently has holography in spades, and only needs more tweaks to be comparable to what I have been hearing from top amps,
Which is soundstage presentation and cleaner lower end.

That being said, I still plan to try make another amp this summer.

Good to know u have plan to build another amp, interest to learn from yours. My MK8 still waiting for the parts to arrive which order some resistors and Mundolf EVO caps n EVO oil caps.
2 days ago, I have heard my friend's newly bought IFI PRO ICAN HEADPHONE AMPLIFIER, that's the best amp I have ever heard to drive HD800s, the background low end very clear punch, soundstage very clear details, I think U should have a try if have any chance

 

[Maxx134]

I know that Coinmaster swears by his massive industrial film caps but that's not practical for me in the stock chassis

That may be because the caps were keeping the cathode voltage stable, as well as also keeping the signature high quality.

2 days ago, I have heard my friend's newly bought IFI PRO ICAN HEADPHONE AMPLIFIER, that's the best amp I have ever heard to drive HD800s, the background low end very clear punch, soundstage very clear details, I think U should have a try if have any chance

I owned the IFI Micro BL that is basically same with a built in dac.
They are excellent amp but still do not provide the soundstage holography of a tube amp.
The MK8 is still better for the HD800.

 

[klnglim]

That may be because the caps were keeping the cathode voltage stable, as well as also keeping the signature high quality.


I owned the IFI Micro BL that is basically same with a built in dac.
They are excellent amp but still do not provide the soundstage holography of a tube amp.
The MK8 is still better for the HD800.

Actually this is totally different, it has 3 internal choices to run this amp, there are solid state, hybrid and individual tube.
I have heard IFI micro BL, it's ok for me but I felt it still too big and heavy as portable use